JPH0342128B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION In a muffler for an internal combustion engine, as shown in FIG. P4
It is well known to have a structure in which an exhaust introduction pipe T1, an exhaust pipe T2, communication pipes T3, T4, etc. are passed through the holes in the plates and fixed.

The present invention relates to a method for assembling and fixing together at least one plate and at least one tube as described above.

As a method for doing so, the applicant has
(Special Publication No. 62-54566). The invention consists of (a) drilling a grommet hole 12 in a predetermined portion of the plate material 1 by burring so that a flange 11 having an inner diameter approximately equal to the outer diameter of the tube material 2 is formed (Fig. 2a); b) Fit the pipe material 2 into the eyelet hole 12 (second b)
(Figure 2c) Holding in a predetermined mounting position using a receiving die 3 (Figure 2c); (c) Prepare a caulking die 4 in which a hole having an inner diameter approximately equal to the outer diameter of the pipe material 2 is formed. (d) Drive the caulking press 4 so that the flange 11 bites into the outer circumferential surface of the tube 2 and is deformed.

As shown in FIG. 2c, a concave portion 41 that engages with the tip end 111 of the flange is formed concentrically with the tube material 2 at the contact portion of the pressing mold 4 with the flange 11 of the plate material.
And if the part of the fixing receiving mold 3 facing the plate material 1 is formed to have a larger diameter than the outer diameter of the flange 11 and is formed into a flat surface, by pressing the pressing mold 4 against the fixing receiving mold 3. , the flange 11 is crushed and double caulked as shown in Fig. 2d, and a part of the caulked portion bites into the outer peripheral surface of the pipe material 2, so that the plate material 1 and the pipe material 2 are firmly connected. .

Furthermore, approximately trapezoidal recesses 31, as shown in FIG.
42, the two members 1 and 2 are joined together by caulking into a substantially triangular shape as shown in FIG. 3b.

This method has the advantage of being simple in equipment and operation, and providing a strong bond between the plate and the tube.

However, since a strong force is applied to press and buckle the flange 11, problems such as bending may occur on the surface of the plate material 1.

In order to eliminate the above-mentioned inconvenience, the present invention is constructed as described in the claims, and the fourth aspect of the present invention is as follows.
The illustrated embodiment will be explained in detail.

A presser die 6 corresponding to the presser die 4 has an outer diameter smaller than that of the presser die 4, and a presser die 7 is prepared in which a hole 71 having approximately the same diameter as the outer diameter of the presser die 6 is formed. Set it in the press die 6 through the hole 71,
The plate material 1 is pressed against the receiving mold 3, and both molds 3,
Hold it between 7 parts.

By pressing the tip 111 of the flange 11 of the plate material 1 with the pressing die 6, the flange 11 begins to deform from the circular arc portion 121 of the eyelet hole 12, and as shown in FIGS. 2d and 3b. As shown in the figure, the inner surface bites into the outer peripheral surface of the pipe material 2 and is caulked,
Both materials 1 and 2 are firmly bonded.

During the caulking drive, the plate material 1 is
Since the flange 11 is sandwiched between the flange 11 and the flange 11, deformation stress of the flange 11 can prevent phenomena such as bending on the plate surface.

61 and 72 are recesses for deformation and caulking.
The receiving mold 3 is also provided with a recess 31 as required, as shown in FIG. 3a.

The flange 11 is formed so as to widen toward the tip 112 on the side of the tip 111, thereby preventing the tip from digging into the gap between the tube material 2 and the press die 6.

Further, by forming a low height portion 113 on the flange 11 as shown in FIG. 5, the depth of the caulked portion biting into the pipe material 2 is reduced by the height. By partially varying the circumferential bite depth in this way, the plate material 1.
By providing a bonding strength in the circumferential direction of the tube material 2, displacement in the circumferential direction can be prevented.

Furthermore, as shown in FIG. 6, by forming unevenness on the flange tip pressing surface 611 of the pressing die 6,
The same effect as the example in FIG. 5 can be obtained.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of a silencer manufactured by the method of the present invention, Figs. 2a to 2d are longitudinal cross-sectional views showing an example process sequence of the method that is related to the invention in the prior application, and Fig. 3a.・Figure 3b is an explanatory diagram of a modification thereof, Figure 4 is a longitudinal cross-sectional view illustrating the implementation procedure of the method of the present invention, Figure 5 is a side view of a part of the plate material, and Figure 6 is a part of the press die. Longitudinal cross-sectional view. 1 is the plate material, 11 is the flange, 12 is the eyelet hole,
2 is a tube material, 3 is a receiving die, 6 is a pressing die, 7 is a holding die, and 61 and 72 are concave portions.

Claims (1)

[Claims] 1. An eyelet hole is formed in a predetermined portion of the plate material so that a flange having an inner diameter approximately equal to the outer diameter of the tube material is formed, and a receiver for fitting the tube material into the eyelet hole. A crimping die is prepared in which a hole having an inner diameter approximately equal to the outer diameter of the tube material and a recess for caulking is formed to hold the tube material in a predetermined mounting position using a mold, and the material is set on the tube material through the hole. Prepare a presser die in which a hole having a diameter approximately equal to the outer diameter of the presser die is formed, set the presser die through the hole in the presser die, press the plate material against the receiver die, and press the plate material against the receiving die. A method for firmly joining a plate material such as a silencer to a pipe material, the method comprising sandwiching the mold between molds and driving the pressing mold so that the flange bites into the outer peripheral surface of the pipe material and deforms it. 2. The method for firmly joining a plate and a tube according to claim 1, wherein a caulking recess is also formed in the plate receiving mold. 3. The method of fixing and joining a plate and a tube according to claim 1, wherein the depth of the deformed caulking of the plate into the circumferential surface of the tube is partially varied.